What is a Tri-mode phone?
Each cellular carrier uses one of several digital formats, and a phone that works on one system will not work on another. Because customers will want to use their phones in many different areas, manufacturers have offered phones that will work with different networks as well as on different frequencies. While tri-mode phones have been around for awhile, it is unlikely that two or three years ago CNS users had tri-mode phones. It is more likely that they have dual mode phones, which will not allow them to get the greatest benefit from the roaming agreements that have been negotiated under the cellular contract. A dual mode phone is a phone that can use at least one digital format and analog. Tri-mode phones operate digitally in the cellular and PCS frequency bands (the PCS band is a different set of frequencies from the cellular band and is used by Sprint), as well as analog .